Remove rails implementation of describe, alias "test" to "it"

Add using Turn with natural language test case names if the library is available (which it will be in Rails 3.1) [DHH]

This reverts commit 79a06225.

this prevents test state from accumulating, resulting in leaked
objects and slow tests due to overactive GC.

Signed-off-by: Nwycats <wycats@gmail.com>

Run `rake bundle` before running tests.

Signed-off-by: NYehuda Katz <wycats@gmail.com>

	This allows for testing rails bootup (files are required, correct constants are
	set, etc...). Currently, this is implemented via forking only, but we will add 
	support for jruby and windows shortly.

Get ActiveSupport::TestCase working with classic Test::Unit and MiniTest. Fix broken Mocha + MiniTest. Assume ruby-core applies patch #771 fixing libraries which extend Test::Unit.

Added ActiveSupport::BacktraceCleaner and Rails::BacktraceCleaner for cutting down on backtrace noise (inspired by the Thoughtbot Quiet Backtrace plugin) [DHH]

Signed-off-by: NJeremy Kemper <jeremy@bitsweat.net>